Liver pathology: cirrhosis, hepatitis, and primary liver tumors. Update and diagnostic problems

Unusual case of liver cirrhosis presenting as a mass compressing the inferior vena cava: A case report

Liver cirrhosis is a significant global health burden, accounting for approximately 2 million deaths per year worldwide. The underlying etiologies of cirrhosis include viral hepatitis (hepatitis B, C, and D), toxins (such as alcohol and drugs), autoimmune diseases, cholestatic conditions (including primary biliary cholangitis and primary sclerosing cholangitis), vascular disorders (such as Budd-Chiari syndrome, sinusoidal obstruction syndrome, and cardiac cirrhosis), and metabolic disorders (including hemochromatosis, nonalcoholic steatohepatitis, and alpha-1 antitrypsin deficiency). Patients with liver cirrhosis typically present with symptoms such as jaundice, scleral icterus, nausea, and vomiting, accompanied by abnormal liver enzyme levels. Other defining features include spider angiomas, caput medusa, and esophageal and/or rectal varices. Abdominal imaging often reveals fibrotic changes within the liver. In this article, we present a case of a 38-year-old female presenting with signs and symptoms of cirrhosis, with subsequent imaging revealing a Porta hepatis mass compressing the inferior vena cava (IVC). The patient underwent a biopsy consistent with liver cirrhosis. This case is unique in the presentation of her liver cirrhosis as a compressive mass rather than the usual fibrotic changes within the liver parenchyma.

LiverMap pipeline for 3D imaging of human liver reveals volumetric spatial dysregulation of cirrhotic vasculobiliary architecture

The liver contains an intricate microstructure that is critical for liver function. Architectural disruption of this spatial structure is pathologic. Unfortunately, 2D histopathology - the gold standard for pathological understanding of many liver diseases - can misrepresent or leave gaps in our understanding of complex 3D structural features. Here, we utilized immunostaining, tissue clearing, microscopy, and computational software to create 3D multilobular reconstructions of both non-fibrotic and cirrhotic human liver tissue. We found that spatial architecture in human cirrhotic liver samples with varying etiologies had sinusoid zonation dysregulation, reduction in glutamine synthetase-expressing pericentral hepatocytes, regression of central vein networks, disruption of hepatic arterial networks, and fragmentation of biliary networks, which together suggest a pro-portalization/decentralization phenotype in cirrhotic tissue. Further implementation of 3D pathological analyses may provide a deeper understanding of cirrhotic pathobiology and inspire novel treatments for liver disease.

Exploring the impact of lipid droplets on the evolution and progress of hepatocarcinoma

Over the past 10 years, the biological role of lipid droplets (LDs) has gained significant attention in the context of both physiological and pathological conditions. Considerable progress has been made in elucidating key aspects of these organelles, yet much remains to be accomplished to fully comprehend the myriad functions they serve in the progression of hepatic tumors. Our current perception is that LDs are complex and active structures managed by a distinct set of cellular processes. This understanding represents a significant paradigm shift from earlier perspectives. In this review, we aim to recapitulate the function of LDs within the liver, highlighting their pivotal role in the pathogenesis of metabolic dysfunction-associated steatotic liver disease (MASLD) (Hsu and Loomba, 2024) and their contribution to the progression towards more advanced pathological stages up to hepatocellular carcinoma (HC) (Farese and Walther, 2009). We are aware of the molecular complexity and changes occurring in the neoplastic evolution of the liver. Our attempt, however, is to summarize the most important and recent roles of LDs across both healthy and all pathological liver states, up to hepatocarcinoma. For more detailed insights, we direct readers to some of the many excellent reviews already available in the literature (Gluchowski et al., 2017; Hu et al., 2020; Seebacher et al., 2020; Paul et al., 2022).

Naringenin suppresses aluminum-induced experimental hepato-nephrotoxicity in mice through modulation of oxidative stress and inflammation

Aluminum is a widely used metal substance in daily life activities that has been shown to cause severe hepato-nephrotoxicity with long-term exposure. Natural dietary flavonoids are being utilized as a newer pharmaceutical approach against various acute and chronic diseases. Naringenin (NAR) has shown efficient therapeutic properties, including effects against metal toxicities. However, the protective efficacy of NAR on aluminum chloride (AlCl3)-induced hepato-renal toxicity needs investigation as aluminum has shown serious environmental toxicity and bioaccumulation behavior. In this study, mice were treated with AlCl3 (10 mg/kg b.w./day) to assess toxicities, and a group of mice were co-treated with NAR (10 mg/kg b.w./day) to assess the protective effects of NAR against hepato-nephrotoxicity. The levels of blood serum enzymes, oxidative stress biomarkers, inflammatory cytokines, and the apoptosis marker caspase-3 were measured using histological examinations. NAR treatment in AlCl3-treated mice resulted in maintained levels of liver and kidney function enzymes and lipid profiles. NAR treatment attenuated oxidative stress by regulating the levels of nitric oxide, advance oxidation of protein products, protein carbonylation, and lipid peroxidation. NAR also replenished reduced antioxidant enzymes such as superoxide dismutase, catalase, glutathione peroxidase, glutathione reductase and reduced the levels of glutathione and oxidized glutathione. NAR regulated the levels of pro-inflammatory cytokines (IL-1β, IL-6, and TNF-α) and elevated the levels of anti-inflammatory cytokines (IL-4, IL-10, and IFN-γ). The histological study further confirmed the protective effects of NAR against AlCl3-induced hepato-renal alterations. NAR decreased the expression of caspase-3 as a mechanism of protective effects against apoptotic damage in the liver and kidney of AlCl3-treated mice. In summary, this study demonstrated the antioxidant and anti-inflammatory properties of NAR, leading to the suppression of AlCl3-triggered hepato-renal apoptosis and histological alterations. The results suggest that aluminum toxicity needs to be monitored in daily life usage, and supplementation of the natural dietary flavonoid naringenin may help maintain liver and kidney health.

Hematological Abnormalities in Cirrhosis: A Narrative Review

Liver cirrhosis remains a major public health issue. Liver fibrosis leading to cirrhosis is the terminal stage of various chronic liver diseases. Inflammatory cytokines are involved in the pathogenesis. Patients with cirrhosis often have hematological abnormalities, such as anemia and thrombocytopenia, which have multifactorial etiologies. Anemia in cirrhosis could be related to bleeding leading to iron deficiency anemia or other nutritional anemia such as vitamin B12 and folate deficiency. The pathophysiology of thrombocytopenia in liver cirrhosis has been postulated to range from splenic sequestration to bone marrow suppression from toxic agents, such as alcohol. It often complicates management due to the risk of bleeding with severely low platelets. This review aimed to highlight pathogenesis of liver cirrhosis, hematological abnormalities in liver cirrhosis, and their clinical significance.

Gut microbiome as a therapeutic target for liver diseases

The prominent role of gut in regulating the physiology of different organs in a human body is increasingly acknowledged, to which the bidirectional communication between gut and liver is no exception. Liver health is modulated via different key components of gut-liver axis. The gut-derived products mainly generated from dietary components, microbial metabolites, toxins, or other antigens are sensed and transported to the liver through portal vein to which liver responds by secreting bile acids and antibodies. Therefore, maintaining a healthy gut microbiome can promote homeostasis of this gut-liver axis by regulating the intestinal barrier function and reducing the antigenic molecules. Conversely, liver secretions also regulate the gut microbiome composition. Disturbed homeostasis allows luminal antigens to reach liver leading to impaired liver functioning and instigating liver disorders. The perturbations in gut microbiome, permeability, and bile acid pool have been associated with several liver disorders, although precise mechanisms remain largely unresolved. Herein, we discuss functional fingerprints of a healthy gut-liver axis while contemplating mechanistic understanding of pathophysiology of liver diseases and plausible role of gut dysbiosis in different diseased states of liver. Further, novel therapeutic approaches to prevent the severity of liver disorders are discussed in this review.

Recent advances in liver-on-chips: Design, fabrication, and applications

The liver is a multifunctional organ and the metabolic center of the human body. Most drugs and toxins are metabolized in the liver, resulting in varying degrees of hepatotoxicity. The damage of liver will seriously affect human health, so it is very important to study the prevention and treatment of liver diseases. At present, there are many research studies in this field. However, most of them are based on animal models, which are limited by the time-consuming processes and species difference between human and animals. In recent years, liver-on-chips have emerged and developed rapidly and are expected to replace animal models. Liver-on-chips refer to the use of a small number of liver cells on the chips to simulate the liver microenvironment and ultrastructure in vivo. They hold extensive applications in multiple fields by reproducing the unique physiological functions of the liver in vitro. In this review, we first introduced the physiology and pathology of liver and then described the cell system of liver-on-chips, the chip-based liver models, and the applications of liver-on-chips in liver transplantation, drug screening, and metabolic evaluation. Finally, we discussed the currently encountered challenges and future trends in liver-on-chips.

Impact of Nanotechnology on Differentiation and Augmentation of Stem Cells for Liver Therapy

The liver is one of the crucial organs of the body that performs hundreds of chemical reactions needed by the body to survive. It is also the largest gland of the body. The liver has multiple functions, including the synthesis of chemicals, metabolism of nutrients, and removal of toxins. It also acts as a storage unit. The liver has a unique ability to regenerate itself, but it can lead to permanent damage if the injury is beyond recovery. The only possible treatment of severe liver damage is liver transplant which is a costly procedure and has several other drawbacks. Therefore, attention has been shifted towards the use of stem cells that have shown the ability to differentiate into hepatocytes. Among the numerous kinds of stem cells (SCs), the mesenchymal stem cells (MSCs) are the most famous. Various studies suggest that an MSC transplant can repair liver function, improve the signs and symptoms, and increase the chances of survival. This review discusses the impact of combining stem cell therapy with nanotechnology. By integrating stem cell science and nanotechnology, the information about stem cell differentiation and regulation will increase, resulting in a better comprehension of stem cell-based treatment strategies. The augmentation of SCs with nanoparticles has been shown to boost the effect of stem cell-based therapy. Also, the function of green nanoparticles in liver therapies is discussed.

Diagnostic accuracy of apparent diffusion coefficient values combined with γ-glutamyl transpeptidase-to-platelet ratio parameters for predicting hepatitis B-related fibrosis

OBJECTIVES

The accuracy of non-invasive liver fibrosis diagnosis based on the apparent diffusion coefficient (ADC) value combined with the γ-glutamyl transpeptidase-to-platelet ratio (GPR) model to predict the stage of hepatitis B-related fibrosis has not been reported. This study aimed to evaluate the diagnostic efficacy of ADC value combined with GPR for liver fibrosis grading.

METHODS

The data of 180 patients with chronic hepatitis B (CHB) diagnosed by liver biopsy were analyzed. The ADC value, GPR, and their combination were assessed in different cirrhosis stages using receiver operating characteristic curve analysis to evaluate their value in diagnosing liver fibrosis.

RESULTS

We observed that liver fibrosis stages were inversely associated with ADC values (r=-0.691, P<0.001), and positively associated with GPR (r=0.502, P<0.001). The area under the curve for diagnostic efficacy of ADC values, GPR, and their combination for F≥2 liver fibrosis was 0.831, 0.749, and 0.858, respectively, and for F≥3 was 0.872, 0.771, and 0.903, respectively. The diagnostic cutoffs of the combination for each stage were -7.07, -12.21 and -37.75, respectively.

CONCLUSIONS

The combined diagnostic tool of ADC and GPR may improve the accuracy of hepatitis B-related liver fibrosis diagnosis, especially for F≥3.

MORPHOLOGICAL FEATURES OF THE LIVER PARENCHYMA IN THE EXPERIMENTAL SUPPLEMENTATION OF RATION WITH THE FOOD ADDITIVES

OBJECTIVE

The aim: The aim of the paper was the experimental study of the morphological features of albino rat hepatocytes after the consumption of the complex of food additives (monosodium glutamate, sodium nitrite, Ponceau 4R) supplemented into the ration and consumed for four weeks.

PATIENTS AND METHODS

Materials and methods: The study was performed on 30 outbred albino rats of both genders, weighing 204±0.67 g. The ration of the experimental animals, supplemented with a combination of food additives, namely, monosodium glutamate, Ponceau 4R, sodium nitrate, was consumed for 1 and 4 weeks. The study of the structure of hepathocytes was carried out on traditional histological preparations and preparations stained with Best's carmine.

RESULTS

Results: Supplementation of ration with the complex of food additives for one week showed the phenomena of fatty degeneration that dominated in hepatocytes, and in a longer consumption of food additives in the ration (for four weeks), the number of liver cells with the phenomena of hydropic degeneration significantly increased, while individual hepatocytes had signs of irreversible destructive changes.

CONCLUSION

Conclusions: Consumption of the complex of food additives supplemented into the standard ration of laboratory animals for 4 weeks leads to a significant change in the dimensions of the liver cells, a decrease in their glycogen content, and a progressive increase in the number of hepatocytes with alterations.

Significance of hepatocyte atypia in liver fine needle aspiration

Fine needle aspiration (FNA) of the liver is frequently the diagnostic procedure of choice for sampling hepatic lesions. One of the main diagnostic challenges in the interpretation of liver FNA is distinguishing dysplastic lesions and well-differentiated hepatocellular carcinoma (WD-HCC) from benign processes, as they share significant cytomorphologic overlap. Furthermore, the diagnosis of HCC often requires evaluation of stroma for invasion, which may not be present on cytology and small needle biopsy specimens. A reporting system for liver cytopathology has yet to be instituted. Without standardized and well-defined criteria for hepatocyte atypia, we recommend limiting the use of atypia in evaluation of liver FNA specimens to describe a diagnosis of exclusion, in which all known benign and neoplastic processes have been ruled out. The cytologic findings on the FNA of a liver nodule may be best reported as atypical hepatocytes in the absence of a core needle biopsy or cell block sufficient to render a definitive diagnosis of HCC.

Molecular Crosstalk between the Hepatitis C Virus and the Extracellular Matrix in Liver Fibrogenesis and Early Carcinogenesis

Simple Summary

In the era of direct-acting antivirals against the hepatitis C virus (HCV), curing chronic hepatitis C has become a reality. However, while replicating chronically, HCV creates a peculiar state of inflammation and oxidative stress in the infected liver, which fuels DNA damage at the onset of HCV-induced hepatocellular carcinoma (HCC). This cancer, the second leading cause of death by cancer, remains of bad prognosis when diagnosed. This review aims to decipher how HCV durably alters elements of the extracellular matrix that compose the liver microenvironment, directly through its viral proteins or indirectly through the induction of cytokine secretion, thereby leading to liver fibrosis, cirrhosis, and, ultimately, HCC.

Abstract

Chronic infection by the hepatitis C virus (HCV) is a major cause of liver diseases, predisposing to fibrosis and hepatocellular carcinoma. Liver fibrosis is characterized by an overly abundant accumulation of components of the hepatic extracellular matrix, such as collagen and elastin, with consequences on the properties of this microenvironment and cancer initiation and growth. This review will provide an update on mechanistic concepts of HCV-related liver fibrosis/cirrhosis and early stages of carcinogenesis, with a dissection of the molecular details of the crosstalk during disease progression between hepatocytes, the extracellular matrix, and hepatic stellate cells.

A large-scale internal validation study of unsupervised virtual trichrome staining technologies on nonalcoholic steatohepatitis liver biopsies

Non-alcoholic steatohepatitis (NASH) is a fatty liver disease characterized by accumulation of fat in hepatocytes with concurrent inflammation and is associated with morbidity, cirrhosis and liver failure. After extraction of a liver core biopsy, tissue sections are stained with hematoxylin and eosin (H&E) to grade NASH activity, and stained with trichrome to stage fibrosis. Methods to computationally transform one stain into another on digital whole slide images (WSI) can lessen the need for additional physical staining besides H&E, reducing personnel, equipment, and time costs. Generative adversarial networks (GAN) have shown promise for virtual staining of tissue. We conducted a large-scale validation study of the viability of GANs for H&E to trichrome conversion on WSI (n = 574). Pathologists were largely unable to distinguish real images from virtual/synthetic images given a set of twelve Turing Tests. We report high correlation between staging of real and virtual stains ([Formula: see text]; 95% CI: 0.84-0.88). Stages assigned to both virtual and real stains correlated similarly with a number of clinical biomarkers and progression to End Stage Liver Disease (Hazard Ratio HR = 2.06, 95% CI: 1.36-3.12, p < 0.001 for real stains; HR = 2.02, 95% CI: 1.40-2.92, p < 0.001 for virtual stains). Our results demonstrate that virtual trichrome technologies may offer a software solution that can be employed in the clinical setting as a diagnostic decision aid.

Non-coding RNA Associated Competitive Endogenous RNA Regulatory Network: Novel Therapeutic Approach in Liver Fibrosis

Liver fibrosis or scarring is the most common pathological feature caused by chronic liver injury, and is widely considered one of the primary causes of morbidity and mortality. It is primarily characterised by hepatic stellate cells (HSC) activation and excessive extracellular matrix (ECM) protein deposition. Overwhelming evidence suggests that the dysregulation of several noncoding RNAs (ncRNAs), mainly long non-coding RNAs (lncRNAs), microRNAs (miRNAs) and circular RNAs (circRNAs) contributes to the activation of HSC and progression of liver fibrosis. These ncRNAs not only bind to their target genes for the development and regression of liver fibrosis but also act as competing endogenous RNAs (ceRNAs) by sponging with miRNAs to form signaling cascades. Among these signaling cascades, lncRNA-miRNA-mRNA and circRNA-miRNA-mRNA are critical modulators for the initiation, progression, and regression of liver fibrosis. Thus, targeting these interacting ncRNA cascades can serve as a novel and potential therapeutic target for inhibition of HSC activation and prevention and regression of liver fibrosis.

A Novel Pathological Scoring System for Hepatic Cirrhosis with Hepatocellular Carcinoma

Purpose

This study aimed to propose an effective quantitative pathological scoring system and to establish nomogram to assess the stage of cirrhosis and predict postoperative survival of hepatocellular carcinoma (HCC) with cirrhosis patients after hepatectomy.

Methods

The scoring system was based on a retrospective study on 163 patients who underwent partial hepatectomy for HCC with cirrhosis. The clinicopathological and follow-up data of 163 HCC with cirrhosis patients who underwent hepatectomy in our hospital from 2010 to 2014 were retrospectively reviewed. A scoring system was established based on the total value of independent predictive factors of cirrhosis. The results were validated using 97 patients operated on from 2011 to 2015 at the same institution. Nomogram was then formulated using a multivariate Cox proportional hazards model to analyze.

Results

The scoring system was ultimately composed of 4 independent predictive factors and was divided into 3 levels. The new cirrhosis system score strongly correlated with Child–Pugh score (r=0.8058, P<0.0001) 3 months after surgery; higher cirrhosis system scores predicted poorer liver function and stronger liver damage 3 months after surgery. Then, a four-factor nomogram for survival prediction was established. The concordance indices were 0.79 for the survival-prediction nomogram. The calibration curves showed good agreement between predictions by the nomogram and actual survival outcomes.

Conclusion

This new scoring system of cirrhosis can help us predict the liver function and liver injury 3 months after surgery, and the nomogram enabled accurate predictions of risk of overall survival in patients of HCC with cirrhosis after hepatectomy.

Cholangitis Lenta: What Hepatologists Need to Know

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Lobular diameters of autopsied dog livers give clues for an appropriate liver biopsy methodology

Hepatobiliary diseases of animals are frequently diagnosed by a combination of imaging, clinical pathology, and histopathology. A standardized surgical liver biopsy protocol, however, has not been established in veterinary medicine with regard to the selection of lobe and site of the liver to yield the most diagnostic information. To address this matter, we histologically examined 33 livers of autopsied dogs from which tissue samples of 4 different lobes as well as 4 different sites of each lobe were prepared. We measured the hepatic lobular diameter (HLD) as an objective variable to refer to the inter-lobar or inter-site difference among the biopsied samples. A measurement of 2,623 hepatic lobules resulted in 1.042 mm as the average of all the HLD values. Statistical analysis further revealed that the HLD tended to be small in a superficial 2 mm area of the liver parenchyma regardless of biopsy location, thus this area should be evaluated carefully by pathologists. The results also suggest that the HLD values of the quadrate lobe may measure smaller than those in the other lobes. Therefore, one would be able to obtain representative data of the entire liver by taking a sample from any single lobe except for the quadrate lobe. HLD measurements are needed in order to accumulate potentially useful information on the microanatomy and pathophysiology of the liver.

Rotavirus Reassortant-Induced Murine Model of Liver Fibrosis Parallels Human Biliary Atresia

BACKGROUND AND AIMS

Biliary atresia (BA) is a devastating neonatal cholangiopathy that progresses to fibrosis and end-stage liver disease by 2 years of age. Portoenterostomy may reestablish biliary drainage, but, despite drainage, virtually all afflicted patients develop fibrosis and progress to end-stage liver disease requiring liver transplantation for survival.

APPROACH AND RESULTS

In the murine model of BA, rhesus rotavirus (RRV) infection of newborn pups results in a cholangiopathy paralleling human BA and has been used to study mechanistic aspects of the disease. Unfortunately, nearly all RRV-infected pups succumb by day of life 14. Thus, in this study we generated an RRV-TUCH rotavirus reassortant (designated as T^R(VP2,VP4) ) that when injected into newborn mice causes an obstructive jaundice phenotype with lower mortality rates. Of the mice that survived, 63% developed Ishak stage 3-5 fibrosis with histopathological signs of inflammation/fibrosis and bile duct obstruction.

CONCLUSIONS

This model of rotavirus-induced neonatal fibrosis will provide an opportunity to study disease pathogenesis and has potential to be used in preclinical studies with an objective to identify therapeutic targets that may alter the course of BA.

Ghrelin Receptor Signaling Is Not Required for Glucocorticoid-Induced Obesity in Male Mice

Chronically elevated levels of glucocorticoids increase food intake, weight gain, and adiposity. Similarly, ghrelin, a gut-secreted hormone, is also associated with weight gain, adiposity, and increased feeding. Here we sought to determine if corticosterone-induced metabolic and behavioral changes require functional ghrelin receptors (GHSR). To do this, we treated male C57BL mice with chronic corticosterone (CORT) mixed in their drinking water for 28 days. Half of these mice received the GHSR antagonist JMV2959 via osmotic minipumps while treated with CORT. In a second experiment, we gave the same CORT protocol to mice with a targeted mutation to the GHSR or their wild-type littermates. As expected, CORT treatment increased food intake, weight gain, and adiposity, but contrary to expectations, mice treated with a GHSR receptor antagonist or GHSR knockout (KO) mice did not show attenuated food intake, weight gain, or adiposity in response to CORT. Similarly, the effects of CORT on the liver were the same or more pronounced in GHSR antagonist-treated and GHSR KO mice. Treatment with JMV2959 did attenuate the effects of chronic CORT on glycemic regulation as determined by the glucose tolerance test. Finally, disruption of GHSR signaling resulted in behavioral responses associated with social withdrawal, potentially due to neuroprotective effects of GHSR activation. In all, we propose that blocking GHSR signaling helps to moderate glucose concentrations when CORT levels are high, but blocking GHSR signaling does not prevent increased food intake, weight gain, or increased adiposity produced by chronic CORT.

Splenic T1ρ as a noninvasive biomarker for portal hypertension

BACKGROUND

There is a need for noninvasive methods for the diagnosis and monitoring of portal hypertension (PH).

PURPOSE

To 1) assess the correlation of liver and spleen T₁ and T_1ρ measurements with portal pressures in patients with chronic liver disease, and 2) to compare the diagnostic performance of the relaxation parameters with radiological assessment of PH.

STUDY TYPE

Prospective.

SUBJECTS

Twenty-five patients (M/F 16/9, mean age 56 years, range 21-78 years) undergoing portal pressure (hepatic venous pressure gradient [HVPG]) measurements.

FIELD STRENGTH/SEQUENCE

1.5T abdominal MRI scan, including T_1ρ and T₁ mapping.

ASSESSMENT

Liver and spleen T_1ρ and T₁ , radiological PH score, and (normalized) spleen length were evaluated.

STATISTICAL TESTS

Spearman correlation of all MRI parameters with HVPG was assessed. The diagnostic performance of the assessed parameters for prediction of PH (HVPG ≥5 mmHg) and clinically significant PH (CSPH, HVPG ≥10 mmHg) was determined by receiver operating characteristic (ROC) analysis.

RESULTS

The mean HVPG measurement was 7.8 ± 5.3 mmHg (PH, n = 18 [72%] including CSPH, n = 9 [36%]). PH score, (normalized) spleen length and spleen T_1ρ significantly correlated with HVPG, with the strongest correlation found for spleen T_1ρ (r = 0.613, P = 0.001). Spleen T_1ρ was the only parameter that showed significant diagnostic performance for assessment of PH (area under the curve [AUC] 0.817, P = 0.015) and CSPH (AUC = 0.778, P = 0.024). Normalized spleen length also showed significant diagnostic performance for prediction of CSPH, with a slightly lower AUC (= 0.764, P = 0.031). The radiological PH score, T_1ρ and T₁ of the liver and T₁ of the spleen, did not show significant diagnostic performance for assessment of CSPH (P > 0.075).

DATA CONCLUSION

Spleen T_1ρ showed a significant correlation with portal pressure and showed improved diagnostic performance for prediction of CSPH compared to radiological assessment. These initial results need confirmation in a larger cohort.

LEVEL OF EVIDENCE

1 Technical Efficacy Stage: 2 J. Magn. Reson. Imaging 2020;52:787-794.

Level and Value of T Cell-derived Circulating Microparticles in Liver Cirrhosis Patients

BACKGROUND/AIM

We examined the hypothesis that T cell-derived-circulating microparticles (MPs) are increased in liver-cirrhosis (LC) patients compared to normal subjects and are also increased in chronic hepatitis compared to acute-decompensated-liver cirrhosis (ADLC).

PATIENTS AND METHODS

A total of 66 LC patients, including 35 with ADLC and 31 with non-decompensated-LC (NDLC), were enrolled in the study. Ten volunteers served as controls.

RESULTS

Flow-cytometric analysis showed that circulating levels of T-cell derived MPs (i.e., total MPs and CD4+/CD8+/CD54+MPs) were higher in LC patients than in the controls (all p<0.003). Total MPs and CD8+MPs were higher in NDLC than in ADLC patients. There were good correlations between CD8+MPs and ADLC as well as between total MPs and chronic hepatitis. Multivariate-linear-regression analysis showed that NDLC was independently predictive of increased circulating CD8+MPs levels (p<0.05) and chronic hepatitis independently predictive of increased circulating total MPs levels (p<0.001)/CD4+MPs (p<0.05).

CONCLUSION

Circulating levels of T-cell-derived MPs were increased in ADLC patients and were even more elevated in NDLC patients compared to healthy-control subjects.

Dysfunction of PLA2G6 and CYP2C44-associated network signals imminent carcinogenesis from chronic inflammation to hepatocellular carcinoma

Little is known about how chronic inflammation contributes to the progression of hepatocellular carcinoma (HCC), especially the initiation of cancer. To uncover the critical transition from chronic inflammation to HCC and the molecular mechanisms at a network level, we analyzed the time-series proteomic data of woodchuck hepatitis virus/c-myc mice and age-matched wt-C57BL/6 mice using our dynamical network biomarker (DNB) model. DNB analysis indicated that the 5th month after birth of transgenic mice was the critical period of cancer initiation, just before the critical transition, which is consistent with clinical symptoms. Meanwhile, the DNB-associated network showed a drastic inversion of protein expression and coexpression levels before and after the critical transition. Two members of DNB, PLA2G6 and CYP2C44, along with their associated differentially expressed proteins, were found to induce dysfunction of arachidonic acid metabolism, further activate inflammatory responses through inflammatory mediator regulation of transient receptor potential channels, and finally lead to impairments of liver detoxification and malignant transition to cancer. As a c-Myc target, PLA2G6 positively correlated with c-Myc in expression, showing a trend from decreasing to increasing during carcinogenesis, with the minimal point at the critical transition or tipping point. Such trend of homologous PLA2G6 and c-Myc was also observed during human hepatocarcinogenesis, with the minimal point at high-grade dysplastic nodules (a stage just before the carcinogenesis). Our study implies that PLA2G6 might function as an oncogene like famous c-Myc during hepatocarcinogenesis, while downregulation of PLA2G6 and c-Myc could be a warning signal indicating imminent carcinogenesis.

The fibrogenic process and the unleashing of acute-on-chronic liver failure

Acute-on-chronic liver failure (ACLF) is a life-threatening condition characterized by a rapid deterioration of previously well-compensated chronic liver diseases. One of the main obstacles in ACLF is the lack of knowledge of the pathogenesis and specific broad-spectrum treatments. An excessive systemic inflammatory response has been proposed to explain the pathogenesis of ACLF; this hypothesis involves stellate cells, which are implicated in many liver homeostatic functions that include vitamin A storage, regulation of sinusoidal blood flow, local inflammation, maintenance of the hepatocyte phenotype and extracellular matrix remodeling. However, when there is damage to the liver, these cells are the main target of the inflammatory stimulus, as a result, the secretion of the extracellular matrix is altered. Activated hepatic stellate cells raise the survival of neutrophils by the stimulation of granulocytes colonies and macrophages, which exacerbates liver inflammation and promotes damage to hepatocytes. Elevation of pathogen-associated molecular patterns is related to liver damage by different pathophysiological mechanisms of decompensation, showing ballooning degeneration and cell death with a predominance of cholestatic infection. Moreover, patients with ACLF present a marked elevation of C-reactive protein together with an elevation of the leukocyte count. Chronic liver disease is a complex pathological state with a heterogeneous pathophysiology in which genetic factors of the host and external triggers interact and culminate in hepatic insufficiency. The better understanding of such interactions should lead to a better comprehension of the disease and to the discovery of new treatment targets that will make acute decompensations preventable and even decrease mortality.

Candidate Biomarkers of Liver Fibrosis: A Concise, Pathophysiology-oriented Review

Repair of sustained liver injury results in fibrosis (i.e. the accumulation of extracellular matrix proteins), and ultimately the complete distortion of parenchymal architecture of the liver, which we call cirrhosis. Detecting and staging of fibrosis is thus a mainstay in the management of chronic liver diseases, since many clinically relevant decisions, such as starting treatment and/or monitoring for complications including hepatocellular carcinoma, may depend on it. The gold standard for fibrosis staging is liver biopsy, the role of which, however, is questioned nowadays because of cost, hazards and poor acceptance by patients. On the other hand, imaging techniques and/or measurement of direct and indirect serum markers have not proved to be completely satisfactory under all circumstances as alternatives to liver biopsy. Making progress in this field is now more crucial than ever, since treatments for established fibrosis appear on the horizon. Fine dissection of the pathways involved in the pathophysiology of liver diseases has put forward several novel candidate biomarkers of liver fibrosis, such as growth arrest-specific6, Mac-2-binding protein, osteopontin, placental growth factor, growth/differentiation factor 15 and hepatocyte growth factor. All molecules have been suggested to have potential to complement or substitute methods currently used to stage liver diseases. Here, we review the pros and cons for their use in this setting.

Ayurvedic drug induced liver injury

Drug induced liver injury is responsible for 50% of acute liver failure in developed countries. Ayurvedic and homeopathic medicine have been linked to liver injury. This case describes the first documented case of Punarnava mandur and Kanchnar guggulu causing drug induced liver injury. Drug induced liver injury may be difficult to diagnosis, but use of multi-modalities tools including the ACG algorithms, causative assessment scales, histological findings, and imaging, is recommended. Advanced imaging, such as magnetic resonance cholangiopancreatography, may possibly have a greater role than previously reported in literature.

Perinatal Bisphenol A Exposure Induces Chronic Inflammation in Rabbit Offspring via Modulation of Gut Bacteria and Their Metabolites

Emerging evidence suggests that environmental toxicants may influence inflammation-promoted chronic disease susceptibility during early life. BPA, an environmental endocrine disruptor, can transfer across the placenta and accumulate in fetal gut and liver. However, underlying mechanisms for BPA-induced colonic and liver inflammation are not fully elucidated. In this report, we show how perinatal BPA exposure in rabbits alters gut microbiota and their metabolite profiles, which leads to colonic and liver inflammation as well as to increased gut permeability as measured by elevated serum lipopolysaccharide (LPS) levels in the offspring. Also, perinatal BPA exposure leads to reduced levels of gut bacterial diversity and bacterial metabolites (short-chain fatty acids [SCFA]) and elevated gut permeability—three common early biomarkers of inflammation-promoted chronic diseases. In addition, we showed that SCFA ameliorated BPA-induced intestinal permeability in vitro. Thus, our study results suggest that correcting environmental toxicant-induced bacterial dysbiosis early in life may reduce the risk of chronic diseases later in life.

Bisphenol A (BPA) accumulates in the maturing gut and liver in utero and is known to alter gut bacterial profiles in offspring. Gut bacterial dysbiosis may contribute to chronic colonic and systemic inflammation. We hypothesized that perinatal BPA exposure-induced intestinal (and liver) inflammation in offspring is due to alterations in the microbiome and colonic metabolome. The 16S rRNA amplicon sequencing analysis revealed differences in beta diversity with a significant reduction in the relative abundances of short-chain fatty acid (SCFA) producers such as Oscillospira and Ruminococcaceae due to BPA exposure. Furthermore, BPA exposure reduced fecal SCFA levels and increased systemic lipopolysaccharide (LPS) levels. BPA exposure-increased intestinal permeability was ameliorated by the addition of SCFA in vitro. Metabolic fingerprints revealed alterations in global metabolism and amino acid metabolism. Thus, our findings indicate that perinatal BPA exposure may cause gut bacterial dysbiosis and altered metabolite profiles, particularly SCFA profiles, leading to chronic colon and liver inflammation.

IMPORTANCE Emerging evidence suggests that environmental toxicants may influence inflammation-promoted chronic disease susceptibility during early life. BPA, an environmental endocrine disruptor, can transfer across the placenta and accumulate in fetal gut and liver. However, underlying mechanisms for BPA-induced colonic and liver inflammation are not fully elucidated. In this report, we show how perinatal BPA exposure in rabbits alters gut microbiota and their metabolite profiles, which leads to colonic and liver inflammation as well as to increased gut permeability as measured by elevated serum lipopolysaccharide (LPS) levels in the offspring. Also, perinatal BPA exposure leads to reduced levels of gut bacterial diversity and bacterial metabolites (short-chain fatty acids [SCFA]) and elevated gut permeability—three common early biomarkers of inflammation-promoted chronic diseases. In addition, we showed that SCFA ameliorated BPA-induced intestinal permeability in vitro. Thus, our study results suggest that correcting environmental toxicant-induced bacterial dysbiosis early in life may reduce the risk of chronic diseases later in life.

Magnetic resonance imaging and spectroscopy for differential assessment of liver abnormalities induced by Opisthorchis felineus in an animal model

BACKGROUND

European liver fluke Opisthorchis felineus, causing opisthorchiasis disease, is widespread in Russia, Ukraine, Kazakhstan and sporadically detected in the EU countries. O. felineus infection leads to hepatobiliary pathological changes, cholangitis, fibrosis and, in severe cases, malignant transformation of bile ducts. Due to absence of specific symptoms, the infection is frequently neglected for a long period. The association of opisthorchiasis with almost incurable bile duct cancer and rising international migration of people that increases the risk of the parasitic etiology of liver fibrosis in non-endemic regions determine high demand for development of approaches to opisthorchiasis detection.

METHODOLOGY/PRINCIPAL FINDINGS

In vivo magnetic resonance imaging and spectroscopy (MRI and MRS) were applied for differential assessment of hepatic abnormalities induced by O. felineus in an experimental animal model. Correlations of the MR-findings with the histological data as well as the data of the biochemical analysis of liver tissue were found. MRI provides valuable information about the severity of liver impairments induced by opisthorchiasis. An MR image of O. felineus infected liver has a characteristic pattern that differs from that of closely related liver fluke infections. 1H and 31P MRS in combination with biochemical analysis data showed that O. felineus infection disturbed hepatic metabolism of the host, which was accompanied by cholesterol accumulation in the liver.

CONCLUSIONS

A non-invasive approach based on the magnetic resonance technique is very advantageous and may be successfully used not only for diagnosing and evaluating liver damage induced by O. felineus, but also for investigating metabolic changes arising in the infected organ. Since damages induced by the liver fluke take place in different liver lobes, MRI has the potential to overcome liver biopsy sampling variability that limits predictive validity of biopsy analysis for staging liver fluke-induced fibrosis.

Collapsed Reticular Network and its Possible Mechanism during the Initiation and/or Progression of Hepatic Fibrosis

Among the researches on hepatic fibrosis, great attention was paid to both hepatocytes and extracellular matrix (ECM). However, little focus was drawn on reticular fibrous network, which is important for demarcation and support of hepatocytes. The aim of this study was to investigate the change pattern of reticular fibers in hepatic fibrosis/cirrhosis and its underlying mechanism. In this study, thioacetamide (TAA) and bile duct ligation (BDL) were utilized to induce rat hepatic fibrosis respectively, and Human liver cirrhotic microassay was analyzed with IHC to confirm the results in animal experiment and to detect the metalloproteinases (MMPs) expressions. As a result, the reticular fibers decreased markedly after 1 week in TAA and 1 day in BDL treated rats. Multiple representative regulators of MMPs and MMPs increased significantly in their expressions and activities. Further more, in human liver cirrhotic microassay, MMPs expressions also showed similar patterns as that of animal experiment. In Conclusions: Degradation or collapse of reticular fibers in hepatic sinusoid can be considered as a pathological feature during the initiation and/or progression of hepatic fibrosis. Moreover, such degradation is associated with and probably caused by the over/dysregulated expression of MMPs.

Hepatitis B virus and its sexually transmitted infection - an update

Epidemiology: incidence and prevalence: About 5% of the world’s population has chronic hepatitis B virus (HBV) infection, and nearly 25% of carriers develop chronic hepatitis, cirrhosis, and hepatocellular carcinoma (HCC). The prevalence of chronic HBV infection in human immunodeficiency virus (HIV)-infected individuals is 5%-15%; HIV/HBV coinfected individuals have a higher level of HBV replication, with higher rates of chronicity, reactivation, occult infection, and HCC than individuals with HBV only. The prevalence of HBV genotype A is significantly higher among men who have sex with men (MSM), compared with the rest of the population. Molecular mechanisms of infection, pathology, and symptomatology: HBV replication begins with entry into the hepatocyte. Sodium taurocholate cotransporting polypeptide was identified in 2012 as the entry receptor of HBV. Although chronic hepatitis B develops slowly, HIV/HBV coinfected individuals show more rapid progression to cirrhosis and HCC. Transmission and protection: The most common sources of HBV infection are body fluids. Hepatitis B (HB) vaccination is recommended for all children and adolescents, and all unvaccinated adults at risk for HBV infection (sexually active individuals such as MSM, individuals with occupational risk, and immunosuppressed individuals). Although HB vaccination can prevent clinical infections (hepatitis), it cannot prevent 100% of subclinical infections. Treatment and curability: The goal of treatment is reducing the risk of complications (cirrhosis and HCC). Pegylated interferon alfa and nucleos(t)ide analogues (NAs) are the current treatments for chronic HBV infection. NAs have improved the outcomes of patients with cirrhosis and HCC, and decreased the incidence of acute liver failure.

Predicting the severity of liver cirrhosis through clinical parameters

BACKGROUND

Severity of liver cirrhosis plays a vital role in determining an appropriate surgical strategy for HCC treatment. However, preoperative evaluation of the severity of cirrhosis has not been established in a surgical setting. This study aims to develop a model to predict the severity of cirrhosis.

METHODS

Overall, 604 patients with hepatocellular carcinoma (HCC) and hepatitis B virus-related cirrhosis undergoing liver resection from Jan 2005 to Jun 2013 were randomly divided into either the model building group (n = 304) or the test group (n = 300). The severity of cirrhosis of the resected specimens was pathologically staged according to the Laennec scoring system, which sub-classified cirrhosis into either stage F4A, F4B, or F4C.

RESULTS

A logistic regression analysis showed that varicosity, portal vein diameter, spleen thickness, and platelet count were significantly associated with the histologic sub-classification of cirrhosis in the model building group. Based on these four parameters, a scoring model for predicting the severity of cirrhosis was established. The model was then verified in the test group, the areas under the ROC (AUROC) for predicting mild (F4A), moderate (F4B), and severe cirrhosis (F4C) were 0.861 (95% confidence interval [CI], 0.810-0.911), 0.860 (95% CI, 0.819-0.901), and 0.968 (95% CI, 0.951-0.985), respectively. The accuracy of this model in predicting mild, moderate, and severe cirrhosis is 79.3%, 81.0%, and 85.3%, respectively.

CONCLUSIONS

By using this model, the severity of cirrhosis can be reliably staged preoperatively, which will provide more information on cirrhotic livers in surgical settings for the treatment of hepatitis B virus-related HCC.

Differential Expression of SWI/SNF Chromatin Remodeler Subunits Brahma and Brahma-Related Gene During Drug-Induced Liver Injury and Regeneration in Mouse Model

The chromatin remodeling activity of mammalian SWI/SNF complex is carried out by either Brahma (BRM) or Brahma-related gene (BRG-1). The BRG-1 regulates genes involved in cell proliferation, whereas BRM is associated with cell differentiation, and arrest of cell growth. Global modifications of histones and expression of genes of chromatin-remodeling subunits have not been studied in in vivo model systems. In the present study, we investigate epigenetic modifications of histones and the expression of genes in thioacetamide (TAA)-induced liver injury and regeneration in a mouse model. In the present study, we report that hepatocyte proliferation and H3S10 phosphorylation occur during 60 to 72 h post TAA treatment in mice. Furthermore, there was change in the H3K9 acetylation and H3K9 trimethylation pattern with respect to liver injury and regeneration phase. Looking into the expression pattern of Brg-1 and Brm, it is evident that they contribute substantially to the process of liver regeneration. The SWI/SNF remodeler might contain BRG-1 as its ATPase subunit during injury phase. Whereas, BRM-associated SWI/SNF remodeler might probably be predominant during decline of injury phase and initiation of regeneration phase. Furthermore, during the regeneration phase, BRG-1-containing remodeler again predominates. Considering all these observations, the present study depicts an interplay between chromatin interacting machineries in different phases of thioacetamide-induced liver injury and regeneration.

Anatomic pathology of hepatocellular carcinoma: histopathology using classic and new diagnostic tools

Hepatocellular carcinoma can be diagnosed on a needle biopsy of the liver; however, uncertainty may arise because of the inherent complexity of liver histology. This article aims to provide practicing pathologists with tools for the approach to mass-directed liver biopsies clinically concerning for hepatocellular carcinoma. The examination of routine hematoxylin-eosin stains and the use of ancillary histochemical and immunohistochemical stains are discussed. Sections reviewing liver carcinoma with biphenotypic differentiation and the challenge of dysplastic nodules are included.

Histological subclassification of cirrhosis can predict recurrence after curative resection of hepatocellular carcinoma

BACKGROUND

Recurrence of hepatocellular carcinoma (HCC) after curative resection continues to be a major cause of death. This prospective study is designed to investigate whether histological subclassification of cirrhosis using the Laennec system could predict recurrence in patients with hepatitis B virus (HBV)-related HCC after curative resection.

METHODS

Patients with HBV-related HCC who underwent curative resection and showed Laennec stage 3 to 4 were enrolled and the cases with stage 4 were subclassified histologically into three groups (stages 4A, 4B and 4C) according to the Laennec system. Between February 2006 and August 2009, 92 patients were recruited.

RESULTS

Stage 3, 4A, 4B and 4C were identified in 24 (26.1%), 15 (16.3%), 43 (46.7%) and 10 (10.9%) patients respectively. The cumulative incidence rates of recurrence at 1, 2 and 3 years were 24.2%, 40.5% and 55.1% respectively. On multivariate analysis, serum albumin [hazard ratio (HR), 0.528; 95% confidence interval (CI), 0.312-0.891; P=0.017] and Edmondson-Steiner grade III-IV (HR, 3.456; 95% CI, 1.123-10.517; P=0.031) were significantly correlated with early recurrence (<1 year), whereas stage 4C (HR, 5.426; 95% CI, 1.030-28.598; P=0.046) was the only independent risk factor for late recurrence (≥1 year).

CONCLUSIONS

Histological subclassification of cirrhosis using the Laennec system is a significant predictor of late recurrence in patients with HBV-related HCC after curative resection.

Pathogenesis of liver cirrhosis

Liver cirrhosis is the final pathological result of various chronic liver diseases, and fibrosis is the precursor of cirrhosis. Many types of cells, cytokines and miRNAs are involved in the initiation and progression of liver fibrosis and cirrhosis. Activation of hepatic stellate cells (HSCs) is a pivotal event in fibrosis. Defenestration and capillarization of liver sinusoidal endothelial cells are major contributing factors to hepatic dysfunction in liver cirrhosis. Activated Kupffer cells destroy hepatocytes and stimulate the activation of HSCs. Repeated cycles of apoptosis and regeneration of hepatocytes contribute to pathogenesis of cirrhosis. At the molecular level, many cytokines are involved in mediation of signaling pathways that regulate activation of HSCs and fibrogenesis. Recently, miRNAs as a post-transcriptional regulator have been found to play a key role in fibrosis and cirrhosis. Robust animal models of liver fibrosis and cirrhosis, as well as the recently identified critical cellular and molecular factors involved in the development of liver fibrosis and cirrhosis will facilitate the development of more effective therapeutic approaches for these conditions.

Reticulin loss in benign fatty liver: an important diagnostic pitfall when considering a diagnosis of hepatocellular carcinoma

Reticulin stains are commonly used in surgical pathology to assess mass lesions for the possibility of hepatocellular carcinoma. The loss of normal reticulin staining can help support a diagnosis of hepatocellular carcinoma, and this stain has proven to be particularly helpful on limited biopsies and fine-needle aspirates. However, an underappreciated diagnostic pitfall is that non-neoplastic liver tissue can also show reticulin loss when there is fatty change. To further characterize this important diagnostic pitfall, reticulin staining was studied in cases of nonalcoholic steatosis, nonalcoholic steatohepatitis, and hepatic adenomas with fatty change. A total of 112 cases with varying degrees of steatosis were collected from 4 academic centers, including 49 cases of steatosis, 49 cases of steatohepatitis, and 14 hepatic adenomas with fatty change. Steatosis was graded as mild (5% to 30% macrovesicular steatosis), moderate (31% to 60%), and marked (>60%). Reticulin stains were scored as the number of foci with diminished reticulin staining in 10 hpf. A focus of diminished reticulin was scored when the extent of reticulin loss was similar to that seen in hepatocellular carcinomas. In the total study set, 28 cases showed mild steatosis, 40 cases showed moderate steatosis, and 44 cases showed marked steatosis. Interestingly, increasing amounts of fat were associated with decreased reticulin staining. For mild steatosis, reticulin loss was rare, with the number of foci of reticulin loss per 10 hpf averaging 0.8 (range, 0 to 3); however, this increased for moderate steatosis, which showed a mean of 3.0 foci per 10 hpf (range, 0 to 5), and was most prominent with marked steatosis, which showed an average of 5.8 foci of reticulin loss per 10 hpf (range, 5 to 8). An almost identical pattern was seen in cases of nonalcoholic steatohepatitis. Overall, reticulin loss was not associated with the degree of inflammation or with the presence or absence of balloon cell change. Reticulin loss also did not correlate with fibrosis stage. In hepatic adenomas, reticulin loss was seen only in areas of fatty change, and decreased reticulin again paralleled the amount of steatosis, with more prominent reticulin loss in those cases with marked steatosis. In conclusion, reticulin loss that reaches levels seen in hepatocellular carcinoma can be seen focally in benign liver tissues with fatty change. Overall, loss of reticulin is more common and more extensive with marked fatty change and does not seem to be linked to inflammation or fibrosis stage. Loss of reticulin can also be seen in hepatic adenomas with fatty change. Increased awareness of this important diagnostic pitfall will help prevent overcalling of reticulin loss when evaluating biopsies and resections of hepatic neoplasms with fatty change.

Liver biopsies in chronic viral hepatitis: beyond grading and staging

CONTEXT

Knowledge of the etiology and pathogenesis of chronic viral hepatitis has grown immensely during the past 50 years. The terminology used to assess liver biopsies with chronic viral hepatitis and the role of the liver biopsy itself have also evolved during this time. Although the focus of much discussion regarding diagnostic assessment of liver biopsies in patients with viral hepatitis has been on grading of activity and staging of fibrosis, each biopsy is also an opportunity to assess many other important features.

OBJECTIVES

To discuss opportunities provided by biopsies to assess features such as the presence of virus-associated premalignant or malignancy-related changes, and the presence of other concomitant diseases, including fatty liver disease of diverse causes, and hemochromatosis, hereditary or otherwise.

DATA SOURCES

The data were obtained from published literature and professional experience.

CONCLUSIONS

The evaluation of liver biopsies with chronic viral hepatitis has evolved beyond grading and staging. Pathologists need to be aware of the other features that may have important clinical implications.

Diagnosis and epidemiology of cirrhosis

Cirrhosis is defined histologically as an advanced form of progressive hepatic fibrosis with distortion of the hepatic architecture and regenerative nodule formation. It may be due to a variety of causes. It can be diagnosed incidentally on liver biopsy or hepatic imaging studies, or patients may present clinically with one or more features of hepatic failure. This article gives the reader a broad overview of the epidemiology, diagnosis, and natural history of cirrhosis; laying the foundation for subsequent articles, which will discuss the diagnosis and management of each of the specific cirrhosis-related complications.

Prevention of hepatocarcinogenesis and increased susceptibility to acetaminophen-induced liver failure in transaldolase-deficient mice by N-acetylcysteine

Although oxidative stress has been implicated in acute acetaminophen-induced liver failure and in chronic liver cirrhosis and hepatocellular carcinoma (HCC), no common underlying metabolic pathway has been identified. Recent case reports suggest a link between the pentose phosphate pathway (PPP) enzyme transaldolase (TAL; encoded by TALDO1) and liver failure in children. Here, we show that Taldo1-/- and Taldo1+/- mice spontaneously developed HCC, and Taldo1-/- mice had increased susceptibility to acetaminophen-induced liver failure. Oxidative stress in Taldo1-/- livers was characterized by the accumulation of sedoheptulose 7-phosphate, failure to recycle ribose 5-phosphate for the oxidative PPP, depleted NADPH and glutathione levels, and increased production of lipid hydroperoxides. Furthermore, we found evidence of hepatic mitochondrial dysfunction, as indicated by loss of transmembrane potential, diminished mitochondrial mass, and reduced ATP/ADP ratio. Reduced beta-catenin phosphorylation and enhanced c-Jun expression in Taldo1-/- livers reflected adaptation to oxidative stress. Taldo1-/- hepatocytes were resistant to CD95/Fas-mediated apoptosis in vitro and in vivo. Remarkably, lifelong administration of the potent antioxidant N-acetylcysteine (NAC) prevented acetaminophen-induced liver failure, restored Fas-dependent hepatocyte apoptosis, and blocked hepatocarcinogenesis in Taldo1-/- mice. These data reveal a protective role for the TAL-mediated branch of the PPP against hepatocarcinogenesis and identify NAC as a promising treatment for liver disease in TAL deficiency.

Fibrolamellar carcinoma presenting as a pancreatic mass: case report and review of the literature

Fibrolamellar carcinoma is a subtype of hepatocellular carcinoma with distinct clinicopathologic features including presentation at a younger age. Although early studies suggested that fibrolamellar carcinoma had a better prognosis than conventional hepatocellular carcinoma, most later studies have found no difference. Patients often have lymph node metastases at presentation in addition to the hepatic primary. We describe an unusual case in a Thai boy who presented with a pancreatic mass that was clinically suspected to be a primary pancreatic tumor, but on biopsy was found to be metastatic fibrolamellar carcinoma. To our knowledge, this manner of presentation has not been previously reported for fibrolamellar carcinoma, nor has metastatic spread to the pancreas.

Frequency and histopathologic basis of hepatic surface nodularity in patients with fulminant hepatic failure

PURPOSE

To determine the frequency and histopathologic basis of hepatic surface nodularity at imaging in patients with fulminant hepatic failure.

MATERIALS AND METHODS

The committee on human research approved this HIPAA-compliant study and waived written informed consent. Thirty-five consecutive patients [24 female [mean age, 38 years +/- 19 (standard deviation); range, 1-67 years] and 11 male [mean age, 29 years +/- 22; range, 2-61 years]] with a mean age of 35 years +/- 20 (range, 1-67 years) who underwent liver transplantation for fulminant hepatic failure at our institution during a 5-year period were retrospectively identified. Pretransplant ultrasonographic (n = 38; three patients each had two studies) and computed tomographic (n = 2) studies were retrospectively and independently reviewed for hepatic surface nodularity. Liver explant histopathologic findings (n = 33; slides unavailable in two patients) were reviewed for cirrhosis and for the combination of alternating foci of confluent regenerative nodules and necrosis. Differences among patients with nodular versus smooth liver surfaces in the proportion with the two histopathologic findings were compared with Fisher exact test. Differences in illness duration and maximum liver biochemical indices were compared with Mann-Whitney Rank Sum test.

RESULTS

Fifteen of 35 patients (43%) demonstrated hepatic surface nodularity at pretransplant imaging, none of whom had cirrhosis at histopathologic examination. One patient with a smooth liver surface had cirrhosis. Compared with those who had a smooth liver surface, patients with hepatic surface nodularity had a significantly greater proportion with the histopathologic finding of a combination of alternating foci of confluent regenerative nodules and necrosis (12 of 14 vs one of 19, P < .001), longer illness duration (31 days +/- 32 vs 13 days +/- 13, P = .029), and lower maximum liver biochemical indices.

CONCLUSION

Hepatic surface nodularity is commonly seen at imaging in fulminant hepatic failure and usually reflects a combination of alternating foci of confluent regenerative nodules and necrosis; this is important because an erroneous radiologic diagnosis of cirrhosis in this setting could adversely affect transplantation status.

In vivo hepatic HB-EGF gene transduction inhibits Fas-induced liver injury and induces liver regeneration in mice: a comparative study to HGF

BACKGROUND/AIMS

It is unknown whether heparin-binding EGF-like growth factor (HB-EGF) can be a therapeutic agent, although previous studies suggested that HB-EGF might be a hepatotrophic factor. This study explores the potential of hepatic HB-EGF gene therapy in comparison with HGF.

METHODS

Mice received an intraperitoneal injection of the agonistic anti-Fas antibody 72 h after an intravenous injection of either adenoviral vector (1x10(11) particles) expressing human HB-EGF (Ad.HB-EGF), human HGF (Ad.HGF) or no gene (Ad.dE1.3), and were sacrificed 24 or 36 h later to assess liver injury and regeneration.

RESULTS

Exogenous HB-EGF was predominantly localized on the membrane, suggesting the initial synthesis of proHB-EGF in hepatocytes. The control Ad.dE1.3-treated mice represented remarkable increases in serum ALT and AST levels and histopathologically severe liver injuries with numerous apoptosis, but a limited number of mitogenic hepatocytes. In contrast, the liver injuries and apoptotic changes were significantly inhibited, but the mitogenic hepatocytes remarkably increased, in both the Ad.HB-EGF- and Ad.HGF-treated mice. More mitogenic hepatocytes and milder injuries were observed in the Ad.HB-EGF-treated mice.

CONCLUSIONS

HB-EGF has more potent protective and mitogenic effects for hepatocytes than HGF, at least for the present conditions. In vivo hepatic HB-EGF gene transduction is therapeutic for Fas-induced liver injury.

Progenitor cells in liver regeneration: molecular responses controlling their activation and expansion

Although normally quiescent, the adult mammalian liver possesses a great capacity to regenerate after different types of injuries in order to restore the lost liver mass and ensure maintenance of the multiple liver functions. Major players in the regeneration process are mature residual cells, including hepatocytes, cholangiocytes and stromal cells. However, if the regenerative capacity of mature cells is impaired by liver-damaging agents, hepatic progenitor cells are activated and expand into the liver parenchyma. Upon transit amplification, the progenitor cells may generate new hepatocytes and biliary cells to restore liver homeostasis. In recent years, hepatic progenitor cells have been the subject of increasing interest due to their therapeutic potential in numerous liver diseases as alternative or supportive/complementary tools to liver transplantation. While the first investigations on hepatic progenitor cells have focused on their origin and phenotypic characterization, recent attention has focused on the influence of the hepatic microenvironment on their activation and proliferation. This microenvironment comprises the extracellular matrix, epithelial and non-epithelial resident liver cells, and recruited inflammatory cells as well as the variety of growth-modulating molecules produced and/or harboured by these elements. The cellular and molecular responses to different regenerative stimuli seem to depend on the injury inflicted and consequently on the molecular microenvironment created in the liver by a certain insult. This review will focus on molecular responses controlling activation and expansion of the hepatic progenitor cell niche, emphasizing similarities and differences in the microenvironments orchestrating regeneration by recruitment of progenitor cell populations or by replication of mature cells.

Identification of a unique gene expression signature that differentiates hepatocellular adenoma from well-differentiated hepatocellular carcinoma

It is often difficult to distinguish hepatocellular adenoma (HCA) from well-differentiated hepatocellular carcinoma (WDHCC) when limited tissue from a needle biopsy is evaluated. The aim of this study was to identify gene expression patterns that can distinguish HCA from WDHCC, with the ultimate goal of discovering novel diagnostic markers. Gene expression profile analysis was performed using Affymetrix U133Plus2 GeneChip microarrays on RNA isolated from frozen tissue of 6 HCA and 8 WDHCC specimens. Statistical analysis of microarray data identified 63 genes whose expression levels were significantly different between HCA and WDHCC. These included 57 genes overexpressed by HCA and 6 overexpressed by WDHCC. Eight genes were chosen for further analysis by quantitative RT-PCR on RNA derived from archived, paraffin-embedded tissue blocks of an independent validation set comprising 9 HCAs and 9 HCCs. Seven of the 8 genes demonstrated average expression differences between HCA and HCC that were concordant with the microarray findings, and their expression pattern correctly classified the 18 tumors into HCA and HCC using unsupervised clustering analysis. Furthermore, immunohistochemical staining performed on a third, independent set of 27 HCAs and 33 HCCs confirmed the expression differences at protein levels for 5 of the genes. Taken together, our data demonstrate significant molecular differences between HCA and WDHCC, despite their morphologic similarity. More importantly, we have identified a unique set of genes whose expression pattern can discriminate between these two types of hepatocellular neoplasms, suggesting the possibility of future development of ancillary molecular and immunohistochemical diagnostic methods.

'Scirrhous' type hepatocellular carcinomas: a special reference to expression of cytokeratin 7 and hepatocyte paraffin 1

AIMS

'Scirrhous' hepatocellular carcinoma (scirrhous HCC) is extremely rare and its characteristics remain unclear. We investigated the clinicopathological and immunohistochemical features of scirrhous HCC, compared with those of ordinary hepatocellular carcinoma (ordinary HCC).

METHODS AND RESULTS

We compared the clinicopathological and immunohistochemical features of 20 resected cases of scirrhous HCC with those of 69 resected cases of ordinary HCC. Scirrhous HCC was characterized by its gross and histological findings, such as a higher proportion of contiguous multinodular type tumours, the absence of a complete fibrous capsule around the tumour, the absence of tumour necrosis and highly preserved portal tracts in the tumour. The immunohistochemical results revealed a significantly higher expression of cytokeratin 7 and a significantly lower expression of hepatocyte paraffin 1 in scirrhous HCC than in ordinary HCC (P<0.0001, respectively). There were no significant differences in proliferative activity and survival curves between the patients with scirrhous HCC and those with ordinary HCC.

CONCLUSION

Scirrhous HCC has several particular gross, histological and immunohistochemical features. In particular, we would like to emphasize the greater immunohistochemical expression of cytokeratin 7 and lower expression of hepatocyte paraffin 1 in scirrhous HCC than in ordinary HCC.

Diagnosis of focal nodular hyperplasia of the liver by needle biopsy

Focal nodular hyperplasia (FNH) of the liver can be a difficult diagnosis to establish in limited diagnostic samples such as a needle-core tissue biopsy, especially for pathologists with limited experience with the lesion. To characterize the features that can be used to make the diagnosis, we reviewed and analyzed the clinicopathologic features of 100 consecutive cases submitted for consultation in which we were confident of the diagnosis of FNH in needle biopsy material. A diagnosis of FNH was correctly made by the contributing pathologist in 24 of the 100 referred cases. Most of the patients (81%) were women of childbearing age with a mean age of 36.75 +/- 9.82 years. Most of the patients (70%) were asymptomatic at diagnosis. The most consistent diagnostic histological feature of FNH in needle biopsy was the presence of ductular reaction with varied intensity at the junction of the fibrous septa with the hepatocellular component, which was present in all 100 cases. Thick abnormal arteries were seen in all but 2 cases (n = 98). Features of chronic cholestasis with cholate stasis and accumulation of copper (demonstrable by the rhodanine stain) and copper-binding protein (demonstrable with the Victoria blue stain) were nearly as common (n = 94). A confident diagnosis of FNH can be made with a needle biopsy, especially if the biopsy is known to come from a mass, and the lesion contains characteristic fibrosis with ductules at the interface between hepatocytes and the fibrous region, prominent arteries, and benign hepatocytes with features of chronic cholestasis.